Pen Needle with Outer Cover

ABSTRACT

A pen needle is enclosed by an outer cover to facilitate installation of a needle bearing hub on a medication pen. The outer cover design reduces or eliminates the likelihood of user contact with the patient end needle or the non-patient end needle during installation and disposal, and provides an audible indication when the hub is fully installed on a medication pen.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a division of U.S. patent application Ser. No.15/100,279, filed on May 27, 2016, which is the U.S. national stageunder 35 U.S.C. 371 of International Patent Application No.PCT/US2014/068567, filed on Dec. 4, 2014, which claims the benefit ofU.S. Provisional Patent Application No. 61/912,538, filed on Dec. 5,2013, all of said prior applications being expressly incorporated hereinby reference.

BACKGROUND OF THE INVENTION Field of the Invention

The invention is the field of medication delivery devices, and inparticular, the invention is directed to medication pens, andspecifically, a pen needle having an outer cover that facilitatesinstallation of the pen needle on a medication pen body and subsequentremoval of the pen needle after use with simultaneous protection of thenon-patient end cannula.

Description of the Related Art

Pen needles are widely used in medication delivery systems forself-administered injectable drugs. In one popular arrangement, the penneedle is provided in an outer cap which is sealed with a layered paperand foil “teardrop label.” The user removes the heat sealed tear-droplabel from the outer cap to expose the proximal or “non-patient’ endneedle located in a cavity on the proximal end of the needle-bearinghub. The exposed needle-bearing hub is then threaded onto a medicationpen such that the non-patient end of the needle pierces the closure ofthe drug storage compartment of the medication pen. The cap is removed,and a smaller needle shield, which slides over a post on the hubsupporting the patient-end needle, is also removed prior to performingan injection. The cap may also be used to remove the needle-hubassembly. Although this system has garnered public acceptance, it isnevertheless desirable to enhance ease of use.

SUMMARY OF THE INVENTION

To avoid difficulty aligning the non-patient end needle with themedication pen to thread the pen needle on the pen, one object of theinvention is to provide a pen needle that self-aligns on the medicationpen during installation. Another object of the invention is to provide acover over the non-patient end needle that may be re-closed after use orafter opening but prior to installation on the pen.

According to one embodiment of the invention, the foregoing objectivesare achieved using a pen needle comprising: an outer cover having aclosed distal end with gently concave sides affording a finger hold andan open proximal end receiving a needle-bearing hub. The needle bearinghub according to this embodiment has an open proximal end defined by aproximal edge aligned with the open proximal end of the outer cover inthe initial state. A flap hinged to the proximal edge of the hub (or tothe open end of the outer cover) has an open position permittinginstallation of the hub on the medication pen and a closed positionenclosing the non-patient end of the needle within the hub (or withinthe outer cover).

The outer cover in this embodiment may be provided with a cut outdefining a flexible strip in a sidewall of the outer cover inboard ofthe open proximal end. A radially inward facing projection on the stripengages contours on a radially outward surface of the hub, so that whenthe outer cover is rotated with respect to the hub the projectiongenerates an audible sound or tactile sensation as the projection on thestrip snaps against the contours on the hub. In some embodiments, thestrip is oriented circumferentially and acts as a pawl mechanism,resisting rotation in the counterclockwise direction.

In another embodiment according to the invention, a pen needle isprovided with an outer cover having a closed distal end with taperedsides affording a finger hold and an open proximal end receiving aneedle-bearing hub. The hub has longitudinal cutouts extending to theproximal edge of the outer cover defining a plurality of projectionsextending proximally from the proximal open end and curved radiallyoutwardly from the hub. In the initial state, with the needle-bearinghub contained in the outer cover, the projections extend beyond theproximal end of the hub and flex slightly inward to protect the userfrom needle stick from the non-patient end needle. Thus, in thisembodiment, projections flex outwardly to release the needle bearing hubduring installation and flex inwardly to contain the needle bearing hubfor storage.

As in the previous embodiment, a flexible strip may be formed in asidewall of the outer cover, provided inboard of the open proximal end,with an inward-facing projection on the strip engaging contours on aradially outward surface of the hub, so that when the outer cover isrotated with respect to the hub, the projection provides sensoryfeedback as it contacts the contours on the hub surface. The strip isoriented circumferentially, so that it acts as a pawl mechanism,resisting rotation in the counterclockwise direction.

In another aspect, the invention is directed to a pen needle outer coverwith an extended proximal end side wall, such that the outer cover sidewall on the proximal end extends beyond the end of the non-patient endneedle. Therefore, the needle is recessed in a cavity on the proximalend of the pen needle and the hub cannot be mated with the medicationpen until the needle is axially aligned with the medication pen. Thisarrangement ensures that the hub is self-aligned with the medicationpen, and that the non-patient end needle is always in the proper axialorientation with respect to the medication pen before the hub is matedonto the medication pen.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts an outer cover and hub assembly according to anembodiment of the invention.

FIG. 2 depicts the outer cover and hub assembly of FIG. 1 in an explodedview.

FIG. 3 depicts a perspective view of an outer cover according to anembodiment of the invention.

FIG. 4 is a cutaway view of the interior of the outer cover of FIG. 3.

FIG. 5 is a perspective view of a hub assembly according to anembodiment of the invention.

FIG. 6 is a perspective view of an outer cover according to anotherembodiment of the invention.

FIG. 7 is an exploded view of the assembly of FIG. 6.

FIG. 8 is a view of the needle-bearing hub according to one embodimentof the invention, showing the distal patient-facing side with a slot forreceiving an inner needle shield.

FIG. 9 is a view of the outer cover and hub assembly of FIG. 1 in theopen position.

FIG. 10 is a pen needle outer cover having an extended side wall.

FIG. 11 is hub adapted to be received in the pen needle outer cover ofFIG. 10.

FIG. 12 shows the engagement of a medication pen with a hub according toFIG. 11 received in pen needle outer cover according to FIG. 10.

FIG. 13 shows the assembly of FIG. 12 with the hub seated on themedication pen.

The figures are schematic for the purpose of illustrating the inventionand not drawn to scale. Features may be enlarged, made smaller,simplified, or eliminated to show how the parts operate according to theinvention.

DETAILED DESCRIPTION OF THE INVENTION

As used herein, the “distal” direction is in the direction of theinjection site, and the “proximal direction” is the opposite direction.The “axial” direction is along the longitudinal axis of the injectiondevice and a “diameter” is generally a diameter with respect to alongitudinal axis. The cannula is generally arranged axially in thedevice. “Radially” is a direction perpendicular to the axial direction.Thus, “radially inward” generally means closer to the needle. An elementextending in the “circumferential direction” means that the elementextends around the circumference; for example threads on a medicationpen are arranged circumferentially on the distal end of the pen.“Medication pen” is used broadly herein to refer to any prefilledmedication delivery device. However, in the most preferred embodiments amedication pen is characterized by having a pen-shaped body and aproximally located thumb button adapted for automatic dosing. A“cut-out” refers to a feature on a surface defined by through-openingsin the surface (inner and outer sides of the surface); a cut-out is saidto be “inboard” if the opening(s) do not extend to the edge of thesurface.

The pen needles according to the invention are provided with a coverthat has tapered sides to facilitate gripping and means to engage thehub in the outer cover so that the two elements rotate together as thehub is installed on a pen needle. The tapered sides are gently concaveto conform approximately to a user's fingers to provide a finger hold.In multiple embodiments, the outer cover is provided with a flexingstrip which contacts contours on the radially outer surface of the hubto provide an audible indication when the outer cover rotates withrespect to the hub after the needle-bearing hub is installed on amedication pen. The strip may have a pawl mechanism so that the outercover resists rotation with respect to the hub in the counter-clockwisedirection when the hub is being removed.

In the embodiment of FIG. 1, outer cover 12 has closed distal end 14formed by concave tapered sides 16 terminating at corners 13. A side ofthe closed distal end opposite the corners is rounded. The tapered sides16 prompt and facilitate gripping with the thumb and index finger, andmay be provided with ribs 18 for this purpose. Sides 16 are described as“gently concave” which is intended to convey that they are shaped tohold with the fingers. Hub 10 is received in the proximal end of theouter cover 12. The exploded view of FIG. 2 shows the orientation of thehub 10 as it fits in the outer cover 12, such that the patient endneedle 22 projects from the patient-facing surface of hub 10 into theinside of outer cover 12. The open end of needle-bearing hub 10 isadapted to be attached to a medication pen. Typically, the hub isadapted with threads, mating with corresponding threads on themedication pen. However, the hub may be adapted with one or moregroove(s) and/or protuberance(s) mating with a corresponding groove(s)and/or protuberance(s) on the medication pen allowing the hub to beinstalled, with or without rotation, and snapped in place. A frictionfit between the hub and medication pen may also be employed. Theattachment means are left to the skill of the artisan to select.Proximal edge 29 defining the open end of hub 10 is aligned with theopen end of the hub cover 12 in the assembled state. Non-patient endneedle 26 is adapted to pierce the septum of a medication cartridgewithin a medication pen body when the hub is installed, and preferablyneedle 26 does not project beyond the plane formed by proximal edge 29of the opening of hub 10. Typically, the patient end needle and thenon-patient end needle are opposite ends of a single stainless steelcannula which is beveled to a point on each end and is affixed in anaxial bore in the hub by adhesive or other means. Reference to a“patient end needle” and a “non-patient end needle” refers to the needlepoints—typically (but not necessarily) they are opposite ends of thesame cannula.

In the embodiment depicted, guard flap 28 is attached to proximal edge29 of hub 10 by hinge 27 which is capable of maintaining at least twopositions: a first open position for installing the hub and a secondclosed position for transporting the hub or discarding after use. In theclosed position, shown in FIG. 1, flap 28 shields the non-patient endneedle 26 from accidental needle stick. In the open state shown in FIG.2, non-patient end needle 26 is exposed, the flap 28 is parallel withthe axis of the needle, and the hub can be threaded onto a medicationdelivery device. Plastic camming and locking elements (not shown) may beprovided on the hinge, bearing against the hub or outer cover to retainthe flap in the first or second position and providing resistance whenthe flap is moved from the first to the second position or from thesecond position to the first. Various hinge constructions are known inthe art which can be adapted for use with injection molded parts, suchas a one-piece living hinge, which may be molded with hub 10, includingflap 28 in the same process. Hinges, including camming elements andlocking fixtures, are disclosed, for example, in U.S. Pat. No.8,887,912, which is incorporated by reference for this purpose. Thehinge design may be left to the person of ordinary skill in the art. Inembodiments, flap 28 may be hinged to outer cover 12 instead of the hub.

In embodiments, flap 28 may be provided with two closed positions: afirst closed position where the flap is held releasably (against theresistance of a camming surface, for example), which allows the hub tobe transported and later opened, so that the needle-bearing hub can beinstalled on a medication pen; and a second position in which the flapis permanently locked in the closed position for disposal. As shown inFIG. 1, a portion 30 of the flap 28 may project outwardly beyond anouter periphery of the outer cover 12 in the first and/or second closedposition.

In the embodiment shown in FIG. 9, outer surface of hub 10 is preferablyprovided with a series of longitudinally arranged grooves 24 whichcooperate with a strip 33 formed on outer cover 12 to provide an audibleindication when the hub is fully installed on the medication pen. In theembodiment shown in FIG. 3, strip 32 is formed between cuts 34 formed atthe open proximal end of the outer cover 12 such that the strip 32 canbe flexed with respect to the outer cover 12. As shown in the interiorcutaway view of FIG. 4, the inside of the outer cover 12 includes aprojection 38 formed on a radially inward surface of the strip 32. Asimilar projection (not shown) may be provided on a radially inwardsurface of strip 33 in the embodiment of FIG. 9. In the case where thehub is attached to the medication pen by rotating the hub onto athreaded connection, the hub and outer cover initially rotate in unison.This may be ensured by providing an interference fit between hub 10 andouter cover 12. Optionally, longitudinal ribs 36 on an interior surfaceof outer cover 12 engage hub 10 to provide the interference fit.However, once hub 10 is fully threaded onto the medication pen, turningthe outer cover further causes the outer cover 12 to rotate with respectto the hub. Flexible strip 32 flexes as the projection 38 is draggedacross the grooves 24 making an audible ratchet sound and/or providing atactile sensation which indicates that the hub is fully installed on themedication pen.

In FIG. 9, strip 33 is oriented circumferentially on the outer coverinboard of the open proximal end, so that strip 33 acts as a pawlmechanism. In this configuration an inward facing projection on strip 33(not shown in FIG. 9) is dragged across contours 24 on the hub when theouter cover is rotated in a clockwise direction after the hub is fullyseated on a medication pen, but reversing the direction causes outercover 12 and hub 10 to rotate together when hub 10 is uninstalled fromthe medication pen for disposal.

Distal face 52 of needle-bearing hub 10 according to differentembodiments of the invention is shown in FIG. 5 and FIG. 8. As seen inFIG. 5 and FIG. 8, distal face 52 of hub 10 is predominately flat, fromthe needle to the periphery of the hub, except for an annular channel 54around the needle. A needle bearing post is recessed in the hub and theannular channel 54 is formed radially around patient end needle 22. Thisannular channel 54 receives an inner needle shield 72 which is providedwith flange 137 (inner shield 72 including flange 137 may besubstantially identical to the embodiment shown in FIG. 7) to situatethe inner shield 72 in the annular channel 54. A hub with a flatpressure pad area is disclosed in U.S. Patent Application PublicationNo. 2009/0069755, which is incorporated by reference in its entirety forthis purpose.

To install a needle bearing hub 10 onto a medication pen using the outercover of FIG. 1, flap 28 is opened from the closed position shown inFIG. 1, until it aligns with the longitudinal axis of the pen needle, inthe position shown in FIG. 9. In this state, the user holds the hub byouter cover 12 and installs internally threaded hub 10 on a medicationpen by rotating the assembly clockwise onto the threaded end of the pen.At a certain point, when hub 10 is fully seated, outer cover 12 rotateswith respect to hub 10 after the hub has been fully installed, and theprojection on strip 33 makes a ratchet sound as it drags across thegrooves 24 on the hub. The outer cover is removed by pulling distally,leaving the hub secured on the medication pen. In this state, themedication pen is readied for administering an injection. The outercover is replaced and turned counterclockwise to remove the hub from thepen. Flap 28 may thereafter be closed to prevent accidental needle stickduring disposal.

FIG. 6 depicts another embodiment of the invention wherein the openproximal end of outer cover 60 assists in grasping the pen needle. Outercover 60 has tapered sides adapted to be gripped by thumb andforefinger, meeting at a curved closed distal end 61. The tapered sidesare gently concave to provide a finger hold, as in the previousembodiment. The tapered sides on the outer cover may be provided withribs 82 to enhance the user's finger hold, meeting at a curved distalend, as shown in FIG. 6. The open proximal end is configured withlongitudinal cut-outs 62 extending to the proximal edge of the outercover defining a plurality of projections 64 extending proximally andcurved radially outwardly from the hub. The projections 64 extend beyondthe hub in the proximal direction when the hub is received fully withinthe outer cover, which protects the user from accidental needle stickfrom the non-patient end needle. Projections 64 are formed to flexoutwardly when cover 60 is pulled off the hub, for example.

The exploded view of FIG. 7 shows hub 10 aligned with inner needleshield 72 in the orientation that these elements are inserted in outercover 60. As in the previous embodiment and as shown in FIG. 7, theouter radial surface of hub 10 may be provided with contours. As shownin FIG. 6, cut-out 84 forms a flap 104 inboard of the open proximal end.The flap is provided with a projection facing radially inward toward thehub (not shown in the Figure). The circumferential orientation ofinboard flap 104 acts as a pawl, resisting rotation of the outer coverwith respect to the hub in the counterclockwise direction.

Distal patient-facing side 52 of hub 10 according to one embodiment ofthe invention is shown in FIG. 8. The effective penetration depth of theneedle is not critical and may be 4 mm to 8 mm, or other standard lengthknown in the art, or a non-standard length. In the embodiment shown, thehub post 57 bearing the needle is embedded in the hub. Annular slot 54is provided around the hub post to accommodate inner needle shield 72.Inner needle shield is provided with a flange 137 to fit securely in theannular slot.

The installation sequence for the needle-bearing hub with the outercover of FIG. 6 is similar to the sequence for the outer cover ofFIG. 1. Before use, hub 10 is within outer cover 60 and projections 64on outer cover 60 extend beyond the distal end of the hub and bendslightly inwardly to protect the user from the non-patient end of theneedle on the hub. Pressing outer cover 60 onto the threaded end of amedication pen causes projections 64 to flare outward, which allowsmedication pen to access hub 10 and for hub 10 to be threaded onto a penwith a clockwise turn of outer cover 60. Turning outer cover 60 beyondthe point at which the hub is fully installed on the pen, causes outercover 60 to rotate with respect to hub 10, creating an audible and/ortactile indication as the flexible strip 104 on the sidewall of theouter cover drags across the contoured surface of hub 10. At this point,outer cover 60 can be removed by pulling it in the distal direction. Theuser removes inner shield 72 covering the needle and the pen isinjection-ready. To remove and store hub 10 for disposal, cover 60 isplaced proximally over the hub, rotated counter-clockwise, and pulleddistally with hub 10 substantially enclosed within projections 64 of theouter cover.

A further aspect of the invention is depicted in FIG. 10 through FIG.13. In FIG. 10, outer cover 100 is provided with an extended proximalside wall 101 extending beyond the tip of non-patient end needle 126when hub 110 is received in outer cover 100. FIG. 11 depicts hub 110,which, in this embodiment, is likewise provided with an extension 111beyond proximal end of non-patient end needle 126. Extended side wall101 prevents inadvertent contact of medication pen 120 with non-patientend needle 126. As shown in FIG. 12 and FIG. 13, the extended flangefeatures 101, 111 are provided so that cover 100 and hub 110, assembledtogether, self-align when installed on medication pen 120. Someclearance is provided between cover 100 and medication pen 120 to permithub 110 to be installed on medication pen 120, by threading or the like.Therefore, the diameter of the proximal end side wall of the outer coveris larger than the diameter of the proximal end of the hub.

In order to prevent non-patient end needle 126 from entering medicationpen 120 at an angle, bending, and possibly failing to reach medicationin a medication compartment therein, extended side wall 101 orients themedication pen as it is inserted in the opening. Any extension of theouter cover in the proximal direction beyond the proximal end of the hubwill assist in guiding outer cover 100, and therefore hub 110, onto amedication pen. For example, an extended side wall of 0.01 inch to 1.00inch is operable. Preferably the side wall extends about 0.20 inch toabout 1.00 inch beyond the needle, and more preferably the extendedflange has a length of about 0.25 inch to about 0.50 inch beyond theproximal end of the non-patient end needle. These dimensions apply tothe proximal end flange portions of cover 101 and proximal end flangeportion of hub 111. Sloped sides 121 on an internal surface of cover 100between proximal end sidewall 101 and a distal portion of cover 100guide medication pen 120 into place irrespective of the angle at whichthe user initially places the assembly on medication pen 120. Where hub110 is provided with extended proximal end sidewall 111, engagement ofhub extended sidewall 111 and outer cover extended sidewall 101 preventshub 110 from moving during installation on a medication pen.Alternatively, or in addition, for this purpose, a friction fit may beprovided between hub 110 and cover 100, for example using sloped inwardprojecting ribs on cover 100 which fit against hub 110. Alternatively alocking feature such as a protuberance or groove on hub 110 maycooperate with a cooperating feature on outer cover 100 to retain hub110 in place during installation. A locking feature, if used, may beovercome by pulling the outer cover distally from the hub afterinstallation.

Cover 100 may be made transparent so a user can view the status of themedication in pen 120. The installed state is depicted in FIG. 13.

The plastic parts described herein, including the hub and outer cover inall the embodiments, are made of polymers suitable for injectionmolding, including without limitation, polypropylene and others known inthe art. Likewise, techniques for injection molding, draw molding andthe like, are well known to those having skill in the art ofmanufacturing medication pens. However, the invention is not limited toany particular production method. The needle is typically a standardgauge surgical stainless steel part. Pen needles according to theinvention are designed to be user-friendly, adapted forself-administered medications, such as insulin, but the invention is notlimited to any particular medication. Likewise, although the 4 mm-8 mminjection depth needle described above is suited for subcutaneousinjection, the invention may also be adapted for use with intradermalinjection.

The foregoing description of the preferred embodiments is not to bedeemed to limit the invention, which is defined by the following claims.The different embodiments are related, such that features recited in thedependent claims are capable of combination with each other, with otherindependent claims, and with other embodiments.

What is claimed is:
 1. A pen needle, comprising: a proximal end needleand a distal end needle received axially on a hub; and an outer coverreceived over the hub covering the distal end needle; the outer coverhaving a proximal end side wall with a diameter larger than a diameterof the proximal end of the hub extending proximally beyond the proximalend of the proximal end needle.
 2. The pen needle according to claim 1,wherein the hub has a proximal end sidewall extending proximally beyondthe proximal end of the needle, and the proximal end sidewall of the hubcontacts the proximal end sidewall of the outer cover to inhibitmovement of the hub during installation on a medication pen.
 3. The penneedle according to claim 1, wherein the outer cover is transparent. 4.The pen needle according to claim 1, wherein the hub does not have aproximal end sidewall extending distally beyond the proximal end needle,and further comprising a frictional fit between the outer cover and thehub, preventing movement of the hub during installation on a medicationpen.
 5. The pen needle according to claim 1, wherein the outer cover hasa sloped internal surface between the proximal end side wall and adistal portion of the outer cover.
 6. The pen needle according to claim1, wherein the proximal end needle and the distal end needle areopposite ends of a cannula positioned in an axial bore of the hub.